Under irrevocable offers based on partial performance, which statement is true?

• A. Partial performance is acceptance in a bilateral contract.
• B. Partial performance can never revoke an offer.
• C. Partial performance may be irrevocable and binding under certain theories.
• D. NY law makes partial performance revocable until completion.

Answer: (C)

The main idea is that offers inviting performance can become irrevocable when partial performance has begun, but only under specific theories. If the offer is for a unilateral contract, the offeree who begins performing cannot be unfairly blocked from completing the contract—the offeror typically cannot revoke once performance has begun, because acceptance is by performance and the contract is formed by completing that performance. Separately, there can be an option-contract theory: if the offeree’s performance is treated as consideration to keep the offer open, an option contract arises, binding the offeror to refrain from revoking for the option period. Either way, partial performance may be irrevocable and binding under the appropriate theory, so the statement captures the correct nuance.

The other options are not accurate because they treat partial performance too rigidly or incorrectly: partial performance isn’t simply acceptance in a bilateral contract, and it isn’t universally revocable under NY law since the unilateral and option theories provide valid exceptions.